Pollution of the food chain by dioxins

The dioxin food crisis in 1999 in Belgium reactivates the debate about subs tances with a very bad reputation. The problem of their control is question ned particularly in foodstuffs. Are the fears about public health founded? After recalling the events of the crisis, chemical structure and properties of dioxins, furanes and PCBs are reviewed. Common sources of contamination are examined, together with ways of exposure and different data concerning their toxicity. The methods of residue analysis and the risk evaluation fo r the public health in the Belgian crisis context are also raised.